w orsley



4 Sheets--Sheet .1. s. L; WORSLEY.

Machine for Threading Screws No. 232,869. Patented Oct. 5,1880.

N-PETERS, FNOTO-UTNOGRAFHER, WASHINGTON, 0 c.

2 t O m 8 m m 5 e e I h .T. S .C W e m n u e You En im & R6 or Wh T u 286 H 1 1H 0 a M MPETENB. PHOTO-UTHOGRAPHER, WASHINGTON D C S. L.WORSLEY.

Machine for Threading Screws. New 332,869. Patemed Oct. 5, i880.

4 Sheets--Sheet 4.

s. L. WORSLEY. Machine for Threading Screws. NO. 232,869.

Patented Oct. 5,1880.

N. PErFJlS, PHOTO-LITNDGRAPMER WASHINGTON, D. C.

UNiTED STATES PATENT prion.

SAMUEL L. WVORSLEY, OF BUFFALO, NEW YORK, ASSIGNOR TO P'LUMB, BURDIOT &BARNARD, OF SAME PLACE.

MACHlNE FOR THREADING SCREWS.

SPECIFICATION forming part of Letters Patent No. 232,869, dated October5, 1880.

' Application filed March 1, 1879.

To all whom it may concern Be it known that I, SAMUEL LORD WORS- LEY, ofBuii'alo,in the county of Erie and State of New York, have made a newand useful invention of Improvements in Machinery for Screwin g or forThreading Bolts, some of which are applicable to oth er purposes; and Ido hereby declare that the following is a full,clear, and exactdescription and specification of the same. i

The principal object of the invention is to take bolts automatically,one at a time, from a bolt-holder, to cut screw-threads upon theirstems, and to discharge them from the machine. The cutting of thescrew-threads, commonly called the screwing or threading of the bolt, iseffected by holding it stationary while a screw-die is simultaneouslyrevolved and advanced upon the bolt-point; and after the screw-thread isout to the requisite extent the revolution of the serew-die is reversedso as to back it off the bolt-point. Hence the screw-die is caused torevolve in alternately opposite directions, and the duration of theperiod of direct movement previous to reversal determines the extent ofthe screw thread formed upon the bolt-stem. It is, however, expedientthat the same machine should be capable of being used to cutscrew-threads of different extents upon bolts; and to this end theobject of some of the improvements hereinafter described is to vary theperiods of reversal of the movement of the revolving shaft or mandrelcarrying the screw-die as required to form screw-threads of differentexteuts that is, screw-threads making different number of turns aroundthe bolt-stems.

The said improvements consist of various combinations of devices, ofwhich devices the following are the principal, viz: Gripers or jaws bymeans of which the bolt-blank is held stationary during the threading orcutting of the screw-thread upon its stem; a die holder or chuck bywhich the screw-die is held and moved; a revolving sliding mandrel bywhich the die'holder and die are turned and caused to advance againstthe bolt-blank so as to cut the screw-thread thereon 5 revolving gearingby which the mandrel is caused to revolve in either of two directionsreversing-gearing by means of which the direction in which the mandrelis caused to revolve is reversed; a leading-cam, or some equivalent orsubstitute therefor, to commence the advance of the screw-die upon thebolt-blank, or vice versa; variablepawl change gearing by means of whichthe times at which the reversing-gear reverses the direction of movementof the re volving mandrel can be varied without necessari] y removingparts of the machine and substitutingothers in their places, and withoutdependence upon the longitudinal movement of either the die-holder orthe gripers which hold the blank to be threaded; a bolt-holder in whichbolt-blanks ready for screwing or threading are held; a bolt-mover bymeans of which the bolt-blanks are taken one at a time from thebolt-holder; one or more stops by which the descent of bolt-blanks inthe boltholder is checked when the lowest bolt-blank is to be taken bythe bolt-mover; transfer fingers or mechanism by means of which aboltblank is transferred from the bolt-mover to the gripers or jaws bywhich the boltblanl; is held during screwing or threading.

Sundry minor devices, hereinafter particularly described, are alsoemployed in making some of the combinations claimed as the invention.The said devices are combined by combining mechanism the constructionand character of which can be vagied as circumstances render expedient,or to suit the views of different constructors.

In order that the invention may be fully understood, I have representedin the accompanying drawings, and will proceed to describe, theprincipal parts of a bolt-threading machine embodying my improvements inthe best form in which they have been embodied at this date.

Figure 1 of said drawings represents a plan of the said machine. Fig. 2represents a front elevation of the same. Fig. 3 represents an end viewof the same. Fig. 4 represents a transverse section of the machine atthe line 00 x of Fig. 1. section of the machine at the line 3 3,! ofFi 1. In some of said figures certain parts are omitted for perspicuity.Figs. 6 to 16 represent views of detached parts of the machine, designated by the same letters as the same parts Fig. 5 represents atransverse 5 9 esasce are designated by in the other figures, and someof said parts being represented upon a larger scale than in the otherfigures.

The working parts of said machine are connected with a strong frame, A,and all the moving parts derive their motion from a drivin g-shaft, B,which is held in suitable bear ings of that frame, and is fitted with abeltpulley, O, to which the driving-beltis applied.

In practice it is coiwenient either to apply a movable tightening-pulley to the driving-belt, so that the latter can be slacked andthe machine stopped by moving the tightening-pulley, or to apply a loosepulley to the drivingshaft, and to employ a belt-shipper to transfer thebelt to and from the driving-pulley and this loose pulley.

The driving-shaft B is connected, by means of coggearing, hereinaftermore particularly described, with a counter-shaft, B, a clutchshaft, Band a revolving hub, B the last being mounted upon a cam-shaft, B

The bolt-blank to be screwed or threaded is held during threadingbetween a pair of gripers or jaws, D D, which grasp its shoulder beneaththe bolt-heads and hold the bolt-blank stationary, or so thatitcannotrevolve. Then a square or angular shouldered bolt-blank is to bethreaded the adjacent faces of the jaws are constructed with angulargrooves fitting the angular shoulders of the bolt-blanks.

The screw-die by which the screw-thread is cut is held by a die-chuck,E, which is secured to the mandrel F. This mandrel is connected bycog-wheels a a with the clutch-shaft B and is also supported in boxes I)b, which permit it to revolve and to slide endwise toward and from thejaws D D. The axis of this mandrel and the axial line of the opening ofthejaws are in the same straight line, so that when the bolt-blank isheld in the jaws it is in line with the axis of the screw-die carried bythe die'chuck E of the revolving mandrel F.

In order that the jaws D D may gripe the bolt-blank and may release it,they are pivoted in an opening ofthejaw-standard I) of the main frame,so that they may open and close like pinchers. In the working machinethe jaws are closed and are permitted to open by means of a slide, whichis connected by toggle-links with their shanks, and the slideisoperated. by means of a cam which is secured to the camshaft B, and isconnected with the slide by means of a lever. A spring also is employedto move back the slide whenever the gripingjaws are to be opened.

As no claim is made to any novelty in the means for opening and closingthe jaws D D, and as the means above referred to are in com mon use foroperating the jaws of other kinds of screw machinery, and as arepresentation of such means in the drawings would increase theircomplexity, it has been deemed better to omit the representation of suchmeans from the drawings.

As before stated, the mandrel F is connected by means of cog-gear a awith the clutch-shaft B so that it is caused to revolve by the action ofthe clutch-shaft. The die-mandrel F and clutch-shaft must, however, becaused to revolve in alternately-opposite directions to cause the die tocut the screw-thread and to back off of the bolt after the screw-threadis cut. In order that the said devices may be revolved alternately inopposite directions while the driving-shaft B continues to revolvein thesame direction, the clutch-shaft is connected with the driving-shaft bymeans of revolving gearing, as follows: Two cog-wheels, a and a aremounted upon the clutch-shaft B with the capacity to turn freely uponit. One of these cog-wheels, a is connected directly with a cog-wheel,a, secured to the driving-shaft B. The other cog-wheel, c of theclutch-shaft is connected with an intermediate cog-wheel, a, secured tothe counter-shaftB, which is caused to revolve in the opposite directionto the driving-shaft by the action of the cog-wheel a upon thatintermediate cog-wheel, a Hence the clutch-wheels a a are caused torevolve continuouslyin reverse directions, and the connection of theclutclrshaft B with one'orother of said clutch-wheels causes theclutch-shaft B, the mandrel F, and the die connected therewith torevolve either forward, as indicated by the arrow .in Fig. 1, orbackward. The clutch-wheels and cog-wheels thus described constitute therevolving mechanism by which the mandrel is caused to revolve in eitherof two directions.

In order that the clutch-shaft B may be connected with the clutch-wheelsa a alternately, the clutch G is provided. This clutch is fitted toslide longitudinally upon the clutch-shaft, but is compelled to turnwith it by means of a feather and groove, and its heads are fitted withclutch-teeth arranged in suitable positions to engage with correspondingteeth protruding from the adjacent faces of the clutclrwheels. Theclutch is shifted upon the cl utch-shaft to engage with one or other ofthe clutch-wheels by means of a double-graded cam, d, which is securedto the counter-shaft B and operates upon the movable pins 0 c of ashifting carriage, d. This carriage is arranged to slide upon a bar, 6?,parallel with the clutch-shaft, and is connected with the clutch Gr byafork, 01. which fits in a circular groove of the clutchbody. Theshifting-pins c 0 are fitted to slide up and down in sockets of theshiftin g carriage, and whenever either pin is dropped downward in itssocket its point is engaged by the shifting-cam d, and the clutch isshifted by the action of that cam, the cam-grade 0 Fig. 16, and pin 0operating to shift the clutch into connection with the clutch-wheel aand. the camgrade 0 Fig. 16, and pin 0 operating to shift the clutchinto connection with the clutch-wheel (o The clutch, the shifting-pins,and the shifting-cam thus effect the reversal of the movement of themandrel, and constitute the reversing gearing or mechanism of themachine.

IIO

In order that the shifting-pins c 0 may be raised and droppedautomatically, two cams, 0 0 are provided, and each of these pin-cams iscaused to operate upon its appropriate pin by means of alever, c and cand a link, 0 and c". The pin-cams c t are secured to the shaft B whichis constructed to revolve in bearings secured to the main frame, and therevolution of the shaft causes the protuberances of the cams to raiseand to drop the pins as required. When the clutch G is in gear witheither clutch-wheel a? or a the mandrel F and the die carried by it willcontinue to re volvein the same direction until the clutch is shifted.The length of time during which the mandrel and die continue to revolvein the same direction should, however, be capable of variation, to adaptthe machine to cutting screw-threads having a different number ofturns'upon the bolt, or extending difl'erent lengths along theboltshank.

In order that the pin-cams c 0 may be operated automaticall y, but mayatthe same time have their operation varied to change or vary the times ofshifting the clutch, their shaft 13 is not connected with thedriving-shaft by means of invariable combining mechanism, but isconnected therewith by means of the following variable-pawl changegearing or mechanism A ratchet-wheel, H, is secured to the end of theshaft B which carries the pineams c 0 and a vibrating pawl, h, isprovided to operate upon this ratchet-wheel. The shank of the lever h ofthe vibrating pawl is connected by a link, h with a crank-pin, b whoseshank is secured in a groove which extends radially across a hub, 7r,secured to the counter-sha-ft- B, so that the crank-pin is adjustabletoward and from the axis of the countershaft which carriesit. Thecontinuous rotation of the counter-shaft B turns the crank-pin h andcauses the pawl h to vibrate at every revolution but the extent to whichthe pawl vibrates, and consequently the amount of movement which itimparts to the ratchetwheel H, to the changegear shaft 13", and to thepin-cams c c secured thereto, depends upon the position in which theadjustable crank-pin If is secured in the groove of the hub h". It theadjustable crank-pin be close to the center of the hub, the vibration ofthe pawl is sufficient to move the ratchet-wheel H but one tooth atatime. Hence under this adjustment of the crank-pin the change-gear shaftB and the cams c. 0 will be turned slowly, and the clutch-shaft,mandrel,and die will run for a comparatively long period in onedirection before beingreversed. By shifting the position of theadjustable crank-pin h in'the groove of the hub h the extent of movementof the pawl h is varied, and it may be made to vibrate to the extent oftwo, three,

or four teeth of the ratchet-wheel, in which cases the latter, thechange-gearshaft B and the pin-cams c 0 will be turned faster, and theclutch will be shifted at shorter intervals,

corresponding with the cutting of screwthreads, making a less number ofturns upon the bolt-shank.

Inorder that the adjustable crank-pin may be readily shifted or adjustedin the groove of the hub h, the crank-pin is in the present exampleconstructed with a tubular body or journal traversed by a screwed stem,having at its inner end the shank which fits in the dovetailed groove ofthe hub and at its outer end a screw-nut, which is slacked to permit thecrank-pin to be adjusted and tightened to secure the adjustablecrank-pin in its place. The same result of varying the extent ofmovement of the pawl may be accomplished by providing the hub h with aseries of holes at dilferent distances from the center of thecounter-shaft, and by shifting the crank-pin from one hole to another.In practice it is generally suflieient to have a machine capable of fourvariations orchanges of the operation of the reversinggearing, andconsequently the present machine is fitted to vary the vibration of thepawl h from one to four ratchet-teeth. brations of the same extent arerequired, the pawl It must be made capable of a greater extent ofvibration; or, if the vibrations are to be made less in extent, theratchet-teeth must be made shorter, or the pawl and teeth may bereplaced by a vibrating clamp operating upon a wheel-rim, like the meansemployed to operate the feed-wheels of sewing-machines. The variation ofthe movement of the pawl or clamp may, if preferred, be effected byshifti ng the leveupin h of the link 71. radially of the pawl-lever h,in place of shifting the crankpin [L3 radially of the counter-shaft; but1 prefer the latter modification. or clamp-wheel, the variable pawl orclamp, and the adjustable crank-pin, or its substitute, by which theextent of movement of the pawl or clamp is varied, constitute thevariablepawl change-gearing of the machine.

When the mandrel F and the screw-die car ried by it are turned in thedirection to cut the screw-thread they must be advanced to the bolt-blank end wise thereof, and must bepushed against it sufficiently to startthe cutting of the thread; or, in place of ZtClVttllGll'lg the mandrel,the griping-jaws, while holding the boltblank from turning, may bearranged to slide, and thus advance the bolt-blank to the screwdie.After the cutting is thus commenced the progressive formation of thescrew-thread by the screw-die will draw the latter with the mandrelforward as long as the turning of the mandrel in the advancing orcutting direction is continued, and thus cause the screw-thread to becut to the requisite extent. In order If a greater number of vi- Theratchet-wheel IOO that the cutting of the screw may be started,

the mandrel F and the screw-die are advanced or moved longitudinallytoward the gripers or jaws l) D by means of a leading-cam, I. Thisleading-cam I is secured to the camshaft B and its cam-grade 1?, Fig. 9,operates upon the mandrel F through the intervention of the rocking armi, the rock-shaft 4?,to which that rocking arm is secured, the secondrocking arm, i projecting from the rock-shaft, the slide 1', which isoperated by the second rocking arm, the sliding piston-rod i and the armi of the piston-rod, which last arm acts upon the end of the mandrel F.The arm i of the piston-rod is fitted with an adjusting-screw, 6 so thatthe screw-die carried by the die-chuck E of the mandrel may be adjustedto its proper position relatively to the bolts to be operated upon. Thepiston i is fitted with a spring, '6 to move the piston 41 back to itsstarting position whenever the leading-cam permits such action. It isalso expedient to apply a similar spring to the mandrel F to insure itsremoval from the point of the bolt after the screw-die has backed offthereof.

The time at which the leading-cam operates to do its work depends uponthe time at which the mandrel is connected with the advancingclutch-wheel a Hence, if the latter time be varied, the former shouldvary with it. In order that the leading-cam may act in concert with thevariation of the movement of the mandrel due to the action of the changegearing or mechanism before described, the lead ing-cam I is operated atintervals, succeeded by intervals of rest. To this end the camshaft B,that carries the leading-cam, is connected with the revolvingdriving-hub B (or some substitute therefor,) by means of a clutch, J,which is engaged with the driving-hub B when the leading-cam is to bedriven, and is disengaged from the driving-hub when the leading-cam isto remain at rest. In order, moreover, that the same change mechanismwhich controls the reversing-clutch Gr may also control the action ofthe leading-cam I, the clutch J, that connects the cam shaft 13 with itsdriving-hub B is operated by a cam, K, secured to the change-gear shaftB This clutchcam K operates upon the clutch through the intervention ofthe lever k, the rod and the clutch-fork V, which engages in aring-groove of the clutch J. The clutchcam K, in the present case, isarranged to disengage the clutch when the leading-cam is to stop acting,and to permit the clutch to engage with the driving-hub J when theleadingcam is to commence acting, a spring, 10 being provided to movethe clutch into engagement with the driving-hub whenever the clutchcam Kpermits this operation.

If itis preferred that the griping-jaws should advance the bolt-blank tothe screw-die, the mandrel need not be constructed to slide endwise; butthe standard which carries the griping-jaws should be constructed toslide upon the frame, and should be connected with the leading cam so asto be operated by it, this construction being an equivalent for thatrepresented iu the drawings.

In order that the bolt-blank to be screwed or threaded may be presentedto the gripingyaws D D automatically at the proper times, a magazine orbolt-holder, L, is provided to contain a supply of bolt-blanks, andmechanism is provided to take one bolt at a time from this bolt-holderand present it to the gripingjaws D D, which hold the bolt-blank fromrevolving during threading. The bolt-holder L consists mainly of twoslabs, l 1, connected at,

their rear ends, with a space between them little wider than thethickness of a bolt-stem, so that the bolt-blanks will lie horizontallyin a column one above the other in said cavity, and will easily slipdown the same when the lowest bolt is removed. The heads of theboltblanks protrude from the cavity, and are held in place by ahead-piece, l, which, with two cheek-pieces, Z Z forms the connection ofthe side slabs of the bolt-holder at its head. The heads of thebolt-blanks are thicker than the stems thereof. Gonsequentl y the columnof superimposed bolts assumes a curved form resembling the spokes of awheel, and the headpiece l and adjacent ends of the side slabs arecurved correspondingly.

In order that the lowest bolt in the boltholder maybe taken therefrom,the boltmover M is provided. This consists of two arms, on m, connectedby a stock, m, with a rock-shaft, m, which is fitted to rock in bearingsconnected with the bolt-holder. The upper edges of the arms are curvedconcentrically with the rock-shaft for the greater part of their length,so that when their curved edges are beneath the cavity of thebolt-holder they act as a stop to prevent the escape of bolt-blanks. Theends of the arms at of the bolt-mover are notched sufficiently to admitthe stem of a bolt-blank. Hence when these notches are brought under thecavity of the bolt-holder they will receive the lowest bolt-blank, andwhen the bolt-mover is subsequently moved by rocking its shaft at thisbolt-blank will be moved laterally from beneath the bolt-holder. Whilethe bolt-blank is thus moved laterally it is prevented from turningaxially in the boltmover by the guard l, which is screwed to the side ofthe bolt-holder, with its lower edge projecting over the track in whichthe angular shoulder of the blank is carried by the boltmover. The blankis also prevented from changing its position longitudinally by means ofa lateral projection, L of the head-piece Z,

and by the side of the guard l, the said projection being at the outerside of the head of the bolt-blank, and the guard being arranged at itsinner side or the shoulder thereof. The bolt-mover is operated at theproper times by means of a cam and a spring acting antagonisticall y.The cam N is secured to the cam-shaft B and operates upon the bolt-moverthrough the intervention of the arm n, the rock shaft a, the secondrocking arm, 11?, the connectingrod a the arm a and the rock-shaft mwhich, as before stated, is connected with the boltmover M. The cam, inthe present case, is arranged to move the bolt-mover backward or*movable stops are provided.

into the position to receive a bolt, while the spring is arranged tomove the bolt-mover forward, or in such manner as to move the boltlaterally from beneaththe bolt-holder. The spring used for this purposein the machine represented in the drawings is a helical spring, M, Fig.7, which is concealed in a tubular cavity of the rock-shaft n, andoperates by torsion upon the head of that rock-shaft.

In order that the whole column of bolts in the bolt holder may not dropimmediately when the notched ends of the bolt-mover are brought beneaththe cavity of the bolt-holder, These stops are by preference two innumber, each consisting of a bar, 0, which is constructed to slidecrosswise of the cavity of the bolt-holder. The ease or guide 0 of eachstop is secured to the side of the bolt-holder, which also is perforatedto permit the endsof the stops to enter the cavity beneath the lowestbolt but one. The stops 0 O are provided with springs 0, which forcethem inward. They are withdrawn from beneath the column of bolts whenthe latter are to be permitted to drop by means of arms 0 one for eachstop, which operate upon studs protruding from the sides of the stops,and are connected with a rock-shaft, 0 which is supported in bearingsconnected with the bolt-holder L. As these stops operate in concert withthe bolt-mover, advantage is taken of this circumstance to withdraw themby connecting their rockshaft 0 with the rockshaft m of the bolt-moverby means of connecting-arms 0 0 Hence whenever the rockshaft of thebolt-mover is operated to move the latter to the position for receivingthe lowest bolt-blank in the bolt-holder the stops 0 O are permitted toenter the cavity of the boltmover and hold the other bolt-blanks fromdropping; and whenever the bolt-mover has been moved laterallysufficiently to carry the lowest bolt from beneath the bolt-holder thestops 0 O are withdrawn to permit the column of bolts to descend in thebolt-holder, so that the lowest bolt-blank is in the proper position todrop into the bolt-mover at its next operation.

In order that the bolt-blank may be transferred from the bolt-mover tothe jaws D D, the transfer-fingers P are provided. These fingers areconnected with a vibrating arm, 1?, the shank of one finger, 1), Figs. 5and 8, being connected rigidly with said arm, while the shank of theother finger, p, is pivoted to said arm, and is provided with a springwhich tends to press the pivoted finger toward the rigid finger, thesaid spring being secured in the head 1) of the arm P. In order thatthese fin gersmay seize the bolt-blank, the inner faces of their pointshave notches formed in them, one of which is \/-formed, and the pointsof the fingers beyond these notches are slightly beveled or slopedoutward, so that when the fingers are pressed down endwise upon theshoulder of a bolt-blank lying in the boltmover these sloping points arecaused to separate and admit the shoulder of thebolt-blank into the finger-notches, where it is held by the action of the fin ger-sprin g. Inorder that these fingers may be moved endwise upon the boltblank, maytransfer it to the griping-jaws, and may return from those jaws, thefingers are moved by vibrating the finger-arm l? by the action of a camand spring. The finger-cam Q is secured to the cam-shaft B so as to berevolved by it, and operates upon the fingerarm P through the arm P androck-shaft P The spring which operates automatically to the cam Q is, inthis example, the same torsion-spring, a Fig. 7, which operates upon thebolt-mover shaft a, one end of said spring bein connected with the endof the rock-shaft P of the vibrating finger-arm through the interventionof a hub, P The object of making the connection through the interventionof this hub is to enable the force of the spring to be adjusted bywinding it up, and for this purpose the face of the hub P is formed withratchet-teeth, any one of which will engage with a corresponding toothformed upon the adjacent face of the hub of the rocking arm P Hence byturning the spring-hub P the spring may be wound up and held in that0011- dition by the engagement-of one of its ratchetteeth with the toothof the finger-arm. The periphery of the finger-cam is so formed as toraise the transfer-fingers high enough to permit the bolt-mover to movea bolt-blank laterally beneath their points, to let the fingers bedepressed upon the bolt-blank so as to seize it, to hold the fingers atrest while the boltmover is withdrawn from the bolt seized by thefingers, and to permit the fingers to. desceud far enough to holdthebolt-blank in line with the axis of the screw-die and the gripingaws.

The action of the fin ger-cam and spring thus far described is to movethe bolt-blank to the axial line of the die and griping-jaws D D. Ifthese jaws are so made and opened as to admit the head of the bolt whenit is moved downward by the fingers, the bolt-blank, while being moveddownward, may be introduced directly between the griping-jaws; but it ispreferred to move the bolt-blank between the jaws by moving it endwisehead foremost. In order that this movement may be efiected the cam Risprovided. This cam has upon one of its sides a grade which operates uponthe lower end of a lever, R, which is pivoted to a standard of the mainframe, and operates at its other end upon the shaft I of the fingerarmP. The action of the cam is to hold the finger-shaft from being movedendwise by the endwise pressure of a spring, and the spring used forsuch endwise movement is the same spring a which has before beendescribed, and which, being compressed endwise between the head of thehollow rock-shaft a and the hub P tends to move that hub, the vibratingfinger-arm P with its fingers P, and the shaft IIO to which said arm issecured endwise in the proper direction to carry the fingers toward thegriping-jaws.

The cam R is secured to the cam-shaft 13 which also carries the cams QN, for controlling the operation of the transferring-fingers P and thebolt-mover M and the grade of the cam lit is so set relatively to thetransfer finger-cam Q that when the transfer fingers have, by theirdownward movement, carried the bolt to the axial line of thegriping-jaws said fingers are .permitted by the cam B to move sidewisetoward the clamping-jaws N, so as to introduce the head of the boltbetween them and hold the blank in this position until the jaws closeupon its square shoulder. Afterthejawsha-ve closed upon the bolt-blankthe cam 1t moves the fingers sidewise away from the jaws to put them inthe proper lateral position for a succeeding operation.

The cams N Q R, which thus control the movement of the bolt-blank to theclampingjaws D D, are all secured to the cam-shaft 13*, which carriesthe leading'cam I, so that the bolt-mover, stops, and transfer-fingersact in concert with each other and with the advance of the die-holder E.Moreover, as the operation of this cam-shaft is controlled by thevariable-pawl change gearing or mechanism, as above described, thelengths of the intervals between the successive operations of feedingbolt-blanks can be changed to permit the threads to be cut a greater orless number of turns upon them.

When the machine is employed to cut the screw-threads of bolts whichhave angular shoulders, either square or polygonal, it is important thatthe bolt should be presented to the jaws with the corners of its angularshoulders in the proper positions to be grasped without bruising incorresponding angular notches of the said jaws. In order to insure thisresult the guard Z} at the side of the boltholder has its lower edgecurved and set above the lower sides of the notches of the bolt-mover adistance slightly greater than the thickness of the angular shoulder ofthe bolt between its opposite sides. Hence the edge of thisshoulder-guard l co-operates with the bolt mover to form a species ofchannel and hold the bolt with the corners of its angular shoulder inthe proper axial positions which they should have to be so presented bythe transfer-fingers to the griping jaws that the angles of theboltshoulder may correspond with the angles of the notches of the jaws.This shoulder-guard is also used in the machine, as before stated, toprevent the bolt from excessive longitudinal movement in the bolt-mover;but a separate guard may be used for that purpose.

In order that the bolt-blank may be moved by the transfer-fingers to itsexact position axially of the spring'jaws and die, the spring a isemployed to cause the descent of the transfer-fingers, and a stop, S, isemployed to limit their descending movement. An adjustable bumper, s,also is fitted to the finger-arm P, to strike the stop S, and theprecise position at which the bolt is presented by the transfer-fingerscan be determined by adjusting this bumper, or, if preferred, by using afixed bumper and making the stop adjustable.

The die by which the threading or screwing is effected is, bypreference, a solid die, and, as before stated, is carried by the diechuck or holder E, which is secured to the head of the revolving mandrelF. The solid die, if made according to the last part of my invention, isa block of steel of conoidal form, as represented at T, Figs. 12, 13,and 14, having upon its periphery several projections or teeth, t,whichfit into corresponding notches formed in the cavity of thedie-chuck E. The butt of this die is fiat, so that it may set trulyagainst the head f of the die-mandrel F, and the die is held there bythe action of the die-chuck, which is composed of the screwed sleeve 0,Fig. 12, and the screwed gland e, the first of which bears against theinner side of the mandrel-head and holds the gland c and the die withinit firmly in place. Dies of this construction are readily forged to theexact shape required by means of suitable forging-dies used in adrop-press, the cavity of the die conforming in form and size with thecavity of the die-chuck in which the die is to be used. The die is thendrilled and cut while held in a die-chuck corresponding with that of thethreading-machine, so that the die will fit the chuck of thethreading-machine without any dressing up. Hence the cost of making diesfor the screw'threadin g machine is reduced to a minimum. 011 the otherhand, the die is free from any groove which requires a milling operationor a planing operation to form it, and which, by nickin g the body ofthe die, renders it liable to crack in the hardening operation to whichthe die is necessarily subjected.

When the threading-machine is to be put to work the variable-pawl changemechanism is adjusted according to the number of turns of screw-threadto be out upon the bolts.

The bolt-blanks are put into the bolt-holder Lby a child, and by theautomatic operation of the machine the bolt-blanks are taken from thebolt-holder, one at a time, by the bolt-mover. The downward movement ofthe column of boltblanks in the bolt-holder is temporarily checked bythe stops. The bolt-blank is presented for the action of thetransfer-fingers, and is seized by them. The bolt-mover is withdrawnfrom beneaththe bolt-blank, which is then transferred to thegriping-jaws. These jaws seize the blank, the die advances upon it andcuts the thread to the required extent, the die backs off of the bolt byreason of the reversal of the movement of the mandrel, and the jaws areopened to permit the threaded bolt to drop. If the bolt hangs in thejaws it is knocked IIO downward from them by the downward move ment ofthe next succeeding bolt-blank carried by the tranfer-fingers.

The adjustment of the machine to the cutting of threads having adifferent number of turns is effected by changing the position of theadjustable crank-pin it as before described.

It is expedient that the time at which the feeding of the bolt commencesrelatively to the time of reversal of movement of the screw-die shouldbe capable of being changed, and this capacity is given in the machineabove described by constructing the cam-grade of the clutch-cam K of twoparts, one of which is movable concentrically of the other, so that thegrade, as a whole, may be lengthened or shortened in the direction ofthe periphery of the cam.

The movable part of the cam-grade is secured by a clamp-screw.

The speed at which the screw-die is advanced or pushed against the pointof the bolt-stem should correspond with the pitch of the screwthrcad tobe formed.

In order that the same leading-cam I may be employed to advance thescrew-dies for screw-threads of different pitches, the rocking arm 6 isslotted, so that the pin i, through which that arm operates upon theslide can be set at greater or less distance from the rockshaft i thuscausing the slide and the mandrel and screw-die which are connected withthat slide to be moved with greater or less speed by the same movementof the leadingcam I.

In order that the bolt-holder and the parts connected with it may be setto the proper positions to suit the bolts to be threaded, the standardU, which supports the bolt-holder, is constructed with a foot, u, whichcan be moved along the rest V, which supports it, and can be secured inany desired position by a screwbolt.

For purposes of adjustment some of the rock ing arms of the machine areconstructed with split hubs, and are secured to their shafts by clampingthe split hubs by clamp-screws. The ends of some of the arms also areslotted, so that the pins by which the arms are connected with otherparts may have their positions changed.

The combination ofthe variable-pawl chan gegearing withreversing-gearing, as above de scribed by me, may be used with advantagein machines for other purposes than threading bolts.

I claim as my invention- 1. The combination, substantially as before setforth, of the change-gearin g shaft and its cams, the ratchet-wheel,variable vibrating pawl, and adjustable crank-pin.

2. The combination, substantially as before set forth, of the clutch,shifting-pins, shiftingcam, pin-cams, camshaft of the change-gearin g,ratchet-wheel, vibrating pawl, and adjustable crank-pin.

3. The combination, substantially as before set forth, of the jaws forholding the bolt blank stationary, the revolving sliding mandrel, theboltholder, the bolt m over, the transfer-fingers, and the variable-pawlchange-gearmg.

4. The combination, substantially as before set forth, of thetransfer-fingers, finger-cam,

- fin ger-cam shaft, drivin g-h ub, and clutch with the variable-pawlchange-gearing.

5. The combination, substantially as before set forth, of thebolt-mover, bolt-mover cam, camshaft, driving-hub, and clutch with thevariable-pawl change-gearing.

6. The combination, substantially as before set forth, of thebolt-holder, the bolt-mover, the stops for checking the descent of thebolts in the bolt-holder, and the transfer-fingers which take the boltfrom the bolt-mover.

7. The combination, substantially as before set forth, of the gripingjaws for holding the blank stationary, the bolt-holder, the boltmover,the transfer-fingers, arranged to move both endwise and sidewise towardand from the gripin g-jaws, and the variable-pawl changegearing.

8. The combination, substantially as before set forth, of thebolt-holder, the bolt-mover, and the shoulder-guard, whose lower edgeoperates on the shoulder of the bolt while in the bolt-mover.

9. The combination, substantially as before set forth, of thebolt-mover, the shoulderguard, and the transfer-fingers.

-10. The combination, substantially as before set forth, of thebolt-holder and bolt-mover with a shoulderguard whose edge operates onthe shoulder of the blank while in the boltmover, and whose side isarranged in the proper position to operate on the inner side of the headof the bolt and prevent excessive longitudinal movement of the bolt.

11. The combination, substantially as before set forth, of thebolt-mover, the shoulderguard, the transfer-fingers, and thegripingjaws, to which the bolt is presented by the tldllSfGPfillgGlS.

12. The combination, substantially as before set forth, of thedie-holder, the revolving sliding mandrel, the leading-cam, the slottedrocking arm, which enables the speed with which the die is advanced tobe varied, and the variable-pawl chan ge-gearin g.

13. The combination, substantially as before set forth, of the conoidalscrew-die with a diechuck consisting of the screwed sleeve and screwedgland operating in connection with the mandrel-head.

Witness my hand this 11th day of February, A. D. 1879.

SAMUEL LORD WORSLEY.

Witnesses A. B. SPRAGUE, ADOLPH HESSLING.

